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Finding the Fourth Proportional to 204.70, 306.82 and 139.70

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Solution

The fourth proportional to 204.70, 306.82 and 139.70 is: 209.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    204.70 : 306.82 = 139.70 : x
  2. Step 2: Convert to fraction form
    204.70/306.82 = 139.70/x
  3. Step 3: Cross multiply
    204.70x = 306.82 × 139.70
  4. Step 4: Simplify right side
    204.70x = 42,862.75
  5. Step 5: Solve for x
    x = 42,862.75/204.70
  6. Step 6: Final answer
    x = 209.39

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.